Roller cutter and lubricator therefor



y 1933- F. 1;. scoTT ET AL 1,909,128

ROLLER CUTTER AND LUBRICATOR THEREFOR Original Filed Feb. 16, 1931 FIG.Z

', FLOYD L. 5cm"!- INVENTOR '1. Lam: L. sxnnzw A'I'TORNEY threaded shank3 for Patented May 16,1933

UNITED STATES PATENT orries FLOYD 1.. score: AND LEW'IS a. GARFIELD,

0F HOUSTON, TEXAS, ASSIGNOBS TO HUGHES TOOL COMPANY, OF HOUSTON, TEXAS,A CORPORATION OF TEXAS ROLLER CUTTER AND LUBBTCLTOR THEREFOR Originalapplication filed February 16, 1931, Serial No. 515,946. Divided andthis application filed february Our invention relates to roller cuttersfor deep well drill bits and includes a means to lubricate the same.

It is an object ofthe invention to provide a lubricator for the bearingsof the cutters which will be automatically operated through the rotationof the cutters to feed the lubricant to the bearings.

It is another object to provide a lubricator which may be containedwithin the head of the drill and arranged so that the fluid ressurethereon is balanced.

It is another object to'provide a means to prevent a loss of lubricantfrom the bearings during the operation of the drill. I

We contemplate a provision of a means to feed the lubricant from thelubricator to the bearings which will tend to feed a uniform supply oflubricant to the bearin gs and operate it only while the drill isrotating.

In the drawing herewith Fig. 1 illustrates a side view partly inelevation and partly in central longitudinal section, illustrating adrill bit equipped with our invention. 2 is a transverse section on theplane 2-2 of Fig. 1.

This application is a division of our c0- pending application No.515,946 filed February 16, 1931.

We have shown the invention as adapted for use partly with the so-calledcone bit. Said bit includes a head 1 longitudinally divided along theplane'2 and having an upper attachment to the drill Each of the halvesof the bit is provided with arotatable cutter 4 beveled face 5 of thehead.

. a flat surface.

is formed a groove extends circumferential- 1y V-shaped. andly about theshaft.

The cutter 4 is formed with a central res I Fig.

drill leading downwardly Serial No. 590,010.

cess shaped to closely engage about the end of the shaft and enclose thesame. It has a V-shaped slot 9 registering with the groove 8 in theshaft to receive a retaining ring 10.

Said ring is approximately rectangular in cross section and made offusible metal adapted to be poured into position while in molten statethrough.a passage indicated at 11 in dotted lines. At the base of thecutter we provide a groove 12 on the inner side thereof to receive apacking ring 13, which is adapted to seal the cutter about the base ofthe shaft and prevent the entrance of fluid to the hearing from theoutside.

T he lubricator which we provide includes a chamber 14 formed in' thehead of the drill and of sufficient capacity to provide lubricant forone run of the drill in the well. Said chamber is cylindrical in shapeand has an outer plug 15 therein to close the outer end of the chamber,except for a passage 16 through said plug to allow the static pressureof liquid in the well to be exerted on the lubricant. We provide apiston 17 in said compartment which is adapted to rest upon the upperside of the lnbricant'and to be forced against the lubricant by thefluid pressure in the well. I g

A passage 18 is formed in the head of the rection longitudinally of theshaft 6. Within the shaft, the passage is enlarged at 20 to. provide avalve chamber for a valve21 which is adapted to close the passage 18through the action of a spring 22 hearing at its outer en against atransverse pin 23. The valve chamber leads to an outer chamber 24 ofsomewhat larger diameter within which'a plunger 25 is fitted. Saidplunger is rounded at its outer i-dly'through the acend and is heldoutwa tion of aspring 26. v

The rounded end of the plunger 25 extends into a recess 27 on the innerside of the cutter. Said recess 27 is best seen in cam 28 in an inclinedd1- mately circular but has axis of the shaft 6. It

' the pl will therefore be end by the and moved inwardly tion of thecutter.

he operation of the lubricator will now be understood. The plunger 25has a, slight clearance within the recess within which it is fitted, sothat lubricant can be forced around the plunger into the cutter. plunger25 is moved inwardly, it will compress the spring 26 andlubricant-within the recess 24 will be squeezed outwardly about ungerinto the recess 27 in the cutter.

21 into the space behind the plunger. We contemplate a heavy type oflubricant will be used and best results have been obtained with thisform of lubricant. The grease will thus forced outwardly around into thebearin between the shaft 6 and the cutter, and when lubricator will bethe pressure of the aim as new is:

1. A drill bit including a head, a cutter s aft thereon, a cuttersurrounding one end of said shaft and rotatable on said shaft as ,abearing, a lubricant container in said head, a passage therefrom to saidbearing, and reciprocating pumping means in said passage operativethrough the rotation of said cutter to feed lubricant to said bearing.

2. A drill bit including a head, a cutter shaft thereon, a cuttersurrounding one end of said shaft and rotatable on said shaft as aaring, a lubricant container in said head, a passage therefrom to saidbearin a c amber connected therewith in said sha t, a plunger in saidchamber, and means on said cutter engaging said plunger to reciprocatethe same and pump lubricant tosaid bearing.

3. A drill bit including a head, a cutter shaft thereon, a cuttersurrounding-one end of said shaftand rotatable on said shaft as acaring, a lubricant container in said head, a passage therefrom tosaid'bearing, a chamr connected therewith in said shaft, a valve in saidchamber normally-closing said passage, a plunger on the downstream sideof said valve, and means on said cutter engaging W at we cl When the bereciprocate the same and pump lubricant mg.

. 4. A drill bit including a head, a cutter I shaft thereon, a cuttersurrounding one end of said shaft and rotatable on said shaft as abearing, a lubricant container in said head, a passage therefrom to saidbearing, a chamr in said passage, a pump in said chamber includin aplunger and a cam on said cutter engaging, said plunger to reciprocatethe same in the rotation of said cutter.

5. A drill bit including a head, a shaft inte- FLOYD L. sco'r'r. LEWISE. GARFIELD.

, gral therewith, a cutter rotatable on said and a cam on said cutterengaging

